Video: How to Print a Mountain Bike

In the second feature of our Fettlers series that looks at some of the most incredible home-made bikes, the focus turns to carbon and specifically the process used by one bike builder to make his own carbon fibre-based mountain bike frames and components.

Adrian Smith uses 3D Printing technology to manufacture the moulds for his CAD-based designs, and then uses carbon fibre fabric to lay over the moulds and produce the final part.

The costs of 3D Printers have come down in recent years and are no longer the preserve of big businesses. In Smith's case, he built his own 3D Printer up from scratch at relatively low cost. Since then he hasn't looked back and has built several inexpensive XC and Downhill bikes under his Carbon Wasp brand name in his home garage in Leeds.

Very interesting. I normally print my plugs, finish them off with some dolphin glaze, then duratec surfacing primer and sand to a gloss finish. Then I make a gelcoat mold of that part.

He certainly must be printing in PLA though. Just looked up the melting temperature of PLA and it melts at 302°F, very close to the required minimum temperature for (most) prepregs of 270°F.

I would be very interested to see the surface of the molds he is printing. From experience, I find it impossible (for my skills) to get a mirror like finish on the part.

I have been messing with composites for the past 15 years, so I find this "garage engineering" amazing.

As for those commenting on a longer video, I am certain a 3 hour documentary could easily be created on all the processes and number of hours he has put into developing this. Saying that, there is no way I would give away that knowledge without some sort of compensation. Perhaps we can fund a Kickstarter to pay him to do a full documentary? I know I would watch is several times.

I had a conversation with the guy that prints my 3D models for me yesterday and he stated that PLA has a lower melting point than ABS (I thought it was the other way around). So I am really curious how he bring the pre-preg to high enough temperatures for it to *fully* cure. Mind you, it will set up at room temperature to something that feels "solid enough" to the touch, but the carbon will not have its full modulus unless it is baked.

Another HUGE issue I just noticed is he is using a 2x2 twill weave, which is definitely nothing I would use for a structural application. He could be adding that for the surface to make it "look pretty", then adding some unidirectional for the inner layers, but then you are just wasting material and adding weight for no good reason.

It is cool what he has done from a hobbyist standpoint, but this would drive a composites engineer crazy (most likely). I am a hobbyist, so I could be wrong, but if anyone is interested in chatting with people from the newb hobbyist all the way to composites engineers, check out www.compositescentral.com

With all due respect, whatever you use is an own preference. I use Wacom Intuous Tablet for 3d modelling and Wacom Cintiq screen for post production, I use mouse very often as well for various things. I am nowhere close to educate anyone what to use, just because I feel tablets are closest to hand drawing feel. Girl next to me draws stuff in AutoCAD and PS using roll bar which my hand drawing teachers would consider a crime for an architect. So if you found something and you are never coming back, you... please do!

It won't. His cost per bike if you factor in materials, electricity, and labour (at minimum wage, even) cost will be orders of magnitude greater than that of big manufacturers on a mass production scale. People often associate 3D printed stuff with lower cost but the printer is only used to make molds. Doing small scale layups by hand is so incredibly time consuming and consumable depleting (vacuum bag and sealant tape as an example) that it can't possibly be more cost effective than producing frames in a large volume industrial setting

100% agree with pwen here - both my homemade carbon bikes would have cost over £2000 for the frame alone should I have factored in the cost of my time into the cost, Also 3D printing equipment and filament/material isn't cheap!

Great little video that's inspiring to any future tech wizards. Granted it's a one off each time he makes a mould but, if you're only making for yourself then why not. If he was making a DH bike I'm sure his actual impregnated carbon layers and curing method would be vastly different to that was shown. XC/trial bikes are more than enough for that method for now I'm guessing. Still, must be amazing to actually design and create your own bike like that.

@jaha222 Mold cost is right or close to this.@sashamtbrider Because they are made of several layers (FDM) or made of tiny material particles melt together (SLM), 3D printed parts are still more brittle than traditional parts. Maybe we can imagine affordable bike frame made with this technology in the far away future but 3D printers will never bet the ratio weight/strenght of a classic carbon process with molds IMO.

That price actually seems a bit low for a complete bike mold. I work in the aerospace industry and some of our carbon fiber molds for parts roughly 1 meter squared are over $500,000! Mind you that's aerospace and not biking. I would have no problem believing if someone said a bike mold cost $40,000 for example.

You can actually print molds that would be cured in an autoclave under pressure at a high temperature with the use of high end 3D printing material, as it can withstand that environment. But for the time being, it's really only practical for low production parts. 3D printing technology is improving at such a fast rate though, and we will see it being used in high production for stuff like this very soon!

You could not run a large scale production out of molds like this. First of all the mold would just melt away in an real autoclave when they material gets cured. (Or cooked how they say in France which is a very charming way to describe this! love it )The tolerances would not be good enough because the mold would flex way too much in production process. Stuff like position of axle or pivot positions would be all over the place.The surface or the mold is too rough so the frame coming out would need too much finishing work which would cause the product to be even more expensive.The production process in this type of mold is to labor intensive as he builds half of every part in a vacuum-bag (like some professional bike builders did in the early nineties) of every part and than combines them which also is not the strongest or lightest way to do this.

So for Adrian that not a big deal because he likes siting down and "carfully" building one bike at a tome, making sure everything is in place and cporrect. He takes his time at sanding and finishing. In between the production steps he just goes over to kitchen for a cup of tee. He can do this because he is building his babes. He's an artist with carbon and what he is doing is awesome i have to say but for a company that has to earn money this would not be an option...

@robwhynot, I'll admit, I've been surprised by what 3D printers have been able to accomplish. I work in defense and we have our 3D printer running non stop on designs that I never would have imagined. But the only people who really believe that it will take over actual machining are hobbyists. There's a reason your friends have that attitude, and there's a reason all big companies that manufacture with carbon fiber or do any molding pay so much money for precision machined parts.

ABS plastic is a material that bonds under heat and pressure. It's still not cutting it.

I think most ppl dont fully understand the 3d printing process, they assume its a magical machine that just manifests things. Nope it has to stack layer upon layer of material, if you understand how composites and their fibers work, you'll realize this is a major fundamental problem with it. It has its applications and im sure it will continue to become more practical as time goes on, but its still not magic.

Plastic will never replace metal/wood.Carbon will never be strong enough for commercial use.Nanotech is sci-fi.Internet will never replace print media.

3D printing has significant limitations based on what we know today. But we learn so much so fast I believe there is a lot of potential for the technology as it continues to mature and innovative minds join the industry.

Of course we're not going to print precision Boeing engine parts tomorrow - likely never - but it's totally naive to think this tech is not going to affect the tool and die industry.

I read on some specialized article that there carbon molds are made from stainless steel.

@sashamtbrider They could print with some sort of "discountinous" carbon fiber reincforce plastic with current 3-d printing techniques. These are not quite as strong and high performance as the "continous" reinfocment of uni-directional carbon fiber. Perhaps they could figure something out though.

@torreyaz there is plenty of 3D printing production applications in aeronautics. They are actually way more expensive then conventional production methods but they allow engineers to build pats with geometries that would not be possible in conventional production methods.

like you said the reason they are expensive is not because its "new" technology but because it is slow technology. Much like any other production method that requires use of Machines the price of parts, no matter if you do molds or actual parts used in a product, the part price is determined by machine hours much like in CNC machining for example. the longer its on the machine the more expensive.

The really exciting thing about this is that if a technology like that is used to create a product there is no reason to do this in china as Machine-hours cost pretty much the same in China or US/Europe so the development of these technologies and wider availability will be positive for domestic production and might lead to some start-up component companies.

Cool stuff for sure, but not applicable for mainstream carbon production. The big guys use steel molds, ovens and bladder processes to get much higher fiber density, tensile strength and perhaps most importantly QC, than wet layup vacuum bagging at room temp could ever do.

Stops short of showing how the frames are actualy made. I dont think the frames are heat cured like a frame clam shelled in a tool grade steel male female mold. Then put into a temperature controlled autoclave oven. does he machine his own BBs and pivot points? How does he deal with the frame as a whole being properly aligned? The 3d printer is a one off machine. How is that cheap?3d printers on the market can not do a whole frame. You could do the same thing with a carved styra foam.

Man he could make a lot of money from what he does.so many people want custom one off bikes and would probably pay him a lot of money!i remember seeing a BTR one off full sus bike they built for some dude at chicksands ( before they made they're own full sus frame!) and that cost that bloke an absolute fortune.

I just got a 2d printer and it is very high end... Shit! There are 3d printers, that are capable of making bikes!
But on the other side the might be flimsy.
But pretty awesome, I could make my own Specialized Enduro!

This is awesome! Gotta give the guy props for doing this all himself. I still don't understand how 3D printers work and how the carbon fibres can be aligned to make a very strong product? Trippy stuff!

I almost reversed engineered my e thirteen chain guard when it got ripped apart by my axle seizing up in my hub. Might as well use my tution money well could mean something by using makerbots and 3D printing MTB parts